Sulphur Creek
Sulphur Creek is an earth dam located in Orange County, California, built in 1966. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Sulphur Creek
The primary purpose of Sulphur Creek is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by County Of Orange (local government). It impounds the Sulphur Creek near Aliso Viejo.
The dam stands 42 feet tall and stretches 485 feet across, creates a reservoir covering 40 acres, and has a maximum storage capacity of 520 acre-feet. Completed in 1966, the structure is well into its service life at over 50 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 09/23/2025.
At 42 feet, this dam is taller than 89% of dams nationwide.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The California dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | California |
| County | Orange |
| Nearest City | Aliso Viejo |
| River/Stream | Sulphur Creek |
| Coordinates | 33.55000, -117.70630 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 42 ft |
| Dam Height | 42 ft |
| Dam Length | 485 ft |
| Year Completed | 1966 (60 years old) |
Storage & Hydraulics
| NID Storage | 520 acre-ft |
| Max Storage | 520 acre-ft |
| Surface Area | 40 acres |
Ownership & Safety
| Purpose | Water Supply |
| Owner | County of Orange |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 09/23/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA00873 |
| Federal ID | CA00873 |
| More Info | State Dam Safety Program |